Chemistry - Stoichiometry Question with Solution | TestHub

Sol. Question Explanation:

Calculating the mass of a product formed when two reactants are mixed.

Concept:

This question is based on the limiting reagent.

Solution:

The reaction is the combustion of phosphorus trisulfide. We find the moles of each reactant to determine the limiting reagent. The mass of the product P₄O₁₀ is calculated based on the moles of the limiting reagent.

The unbalanced reaction is: P₄S₃ + O₂ → P₄O₁₀ + SO₂

The balanced reaction is: P₄S₃ + 8O₂ → P₄O₁₀ + 3SO₂

Molar mass of P₄S₃ = $220g/mol$.

Molar mass of O₂ = $32g/mol$.

Molar mass of P₄O₁₀ = $284g/mol$.

Mass of P₄S₃ = $440g$.

Moles of P₄S₃ = $\frac{440}{220}=2mol$.

Mass of O₂ = $384g$.

Moles of O₂ = $\frac{384}{32}=12mol$.

Limiting reagent:

For P₄S₃: $\frac{2}{1}=2.0$

For O₂: $\frac{12}{8}=1.5$

O₂ is the limiting reagent.

Moles of P₄O₁₀ produced = $12mol{O}_2\times \frac{1mol{P}_4{O}_{10}}{8mol{O}_2}=1.5mol$.

Mass of P₄O₁₀ = $1.5mol\times 284g/mol=426g$.

Final Answer: option (B)